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package egc.ui;

/**
 *
 * @author AJF
 */
import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.*;

public class ExampleGameCanvas extends GameCanvas implements Runnable {

    private boolean isPlay;   // Game Loop runs when isPlay is true 
    private long delay;       // To give thread consistency 
    private int currentX, currentY;  // To hold current position of the 'X' 
    private int width;        // To hold screen width 
    private int height;       // To hold screen height 

// Constructor and initialization 
    public ExampleGameCanvas() {
        super(false);
        width = getWidth();
        height = getHeight();
        currentX = width / 2;
        currentY = height / 2;
        delay = 20;
    }
// Automatically start thread for game loop 

    public void start() {
        isPlay = true;
        Thread t = new Thread(this);
        t.start();
    }

    public void stop() {
        isPlay = false;
    }

// Main Game Loop 
    public void run() {
        Graphics g = getGraphics();
        while (isPlay == true) {

            input();
            drawScreen(g);
            try {
                Thread.sleep(delay);
            } catch (InterruptedException ie) {
            }
        }
    }
// Method to Handle User Inputs 

    private void input() {
        int keyStates = getKeyStates();

// Left 
        if ((keyStates & LEFT_PRESSED) != 0) {
            currentX = Math.max(0, currentX - 1);
        }

// Right 
        if ((keyStates & RIGHT_PRESSED) != 0) {
            if (currentX + 5 < width) {
                currentX = Math.min(width, currentX + 1);
            }
        }

// Up 
        if ((keyStates & UP_PRESSED) != 0) {
            currentY = Math.max(0, currentY - 1);
        }

// Down 
        if ((keyStates & DOWN_PRESSED) != 0) {
            if (currentY + 10 < height) {
                currentY = Math.min(height, currentY + 1);
            }
        }
    }
// Method to Display Graphics 
    private void drawScreen(Graphics g) {
        g.setColor(0xffffff);
        g.fillRect(0, 0, getWidth(), getHeight());
        g.setColor(0x0000ff);
        g.drawString("X", currentX, currentY, Graphics.TOP | Graphics.LEFT);
        flushGraphics();
    }
}